Timeline for For $\mathfrak g$ A Lie algebra of type $ E_7 $, $\mathfrak h $ a Cartan subalgebra and $\Delta$ the resulting root system, does $ Aut(\mathfrak g,\mathfrak h)\rightarrow Aut(\Delta) $ split over the Weyl group?
Current License: CC BY-SA 3.0
9 events
| when toggle format | what | by | license | comment | |
|---|---|---|---|---|---|
| May 1, 2016 at 2:01 | comment | added | Allen Knutson | math.cornell.edu/~allenk/courses/16spring/Construction11.pdf | |
| Apr 30, 2016 at 19:35 | comment | added | LSpice | @AllenKnutson, did these notes make their way over to your Cornell page anywhere? | |
| Sep 25, 2012 at 12:40 | answer | added | Emma Carberry | timeline score: 3 | |
| Sep 7, 2012 at 23:50 | history | edited | Jim Humphreys |
edited tags
|
|
| Sep 7, 2012 at 23:46 | answer | added | Jim Humphreys | timeline score: 3 | |
| Sep 7, 2012 at 14:47 | comment | added | B. Bischof | Thank you for this comment Allen, it was very helpful in answering a question I hadn't been able to ask. | |
| Sep 7, 2012 at 14:06 | answer | added | Alexander Premet | timeline score: 10 | |
| Jul 22, 2011 at 6:17 | comment | added | Allen Knutson | Obviously what one would like is a functorial way of constructing Lie algebras from root systems, and one can't have it because the Weyl group acts on the root system and doesn't act on the group. Which is basically your splitting question. The closest I've seen to a functorial construction is in Jacob Lurie's undergrad thesis math.harvard.edu/~lurie/papers/thesis.pdf and a construction Richard Borcherds explained to me that doubles the root system in order to let the normalizer of the Z-torus act: math.berkeley.edu/~allenk/courses/spr02/261b/notes/… | |
| Jul 14, 2011 at 12:31 | history | asked | Emma Carberry | CC BY-SA 3.0 |